Charged particle beam apparatuses have many functions in a plurality of industrial fields, including, but not limited to, inspection of semiconductor devices during manufacturing, exposure systems for lithography, detecting devices and testing systems. Thus, there is a high demand for structuring and inspecting specimens within the micrometer and nanometer scale.
Micrometer and nanometer scale process control, inspection or structuring, is often done with charged particle beams, e.g. electron beams, which are generated and focused in charged particle beam devices, such as electron microscopes or electron beam pattern generators. Charged particle beams offer superior spatial resolution compared to, e.g. photon beams, due to their short wavelengths.
The signals generated, for example, by a primary electron beam can be collected from practically all parts of a relatively rough surface. Peeling off of individual layers deposited on the specimen or cracks in the specimen might be visible from the edge of the specimen that is to be inspected. It can be desirable to inspect the edge or bevel of the specimen. Further, it may be desirable to inspect a portion of the lower edge or bevel of a specimen or a portion of the bottom surface of the specimen.